Check strap assembly



March 31, 1964 w. A. RANDLETT ET AL 3,126,922

CHECK STRAP ASSEMBLY Filed June 15, 1962 IN VENTORS 32 514; 4.,zmx4mna 4- United States Patent 3,126,922 CHECK STRAP ASSEMBLY Walter A. Randlett and Chester R. Messer, Concord, N.H., assignors to Page Belting Company, Concord, N.H., a corporation of New Hampshire Filed June 15, 1962, Ser. No. 202,753 6 Ctaims. (Cl. 139-465) This invention comprises a new and improved check strap assembly of the type characterized by a U-shaped loop slidable upon a fixed guide rod under the action of the picker stick which is confined and limited in its stroke by the loop.

Check straps of this type are subjected to very severe duty and for many years the textile industry has devoted extensive research and eflfort to increasing the life of the strap. Every advance in that direction is of great importance as it permits the employment of looms operating at increased speed and reduces down time. A gain in speed of only a few picks per minute may make the difference between profit and loss to the manufacturer. It has been found, however, that every increase in loom speed magnifies the severity of duty, reduces the life of the check strap assembly and must be offset by effective improvement of the check strap to meet the manufacturers demand for faster and faster operation.

We have discovered structural improvements which are effective to increase the life and efiiciency of such check strap assemblies and are therefore of outstanding importance and unexpected benefit to the textile industry. We have found that one factor in achieving these improvements consists in substituting for the solid one-piece tie strap or rod, heretofore used in connecting the ends of the loop, a wide tie strip of two sections longitudinally separated at least in part and so arranged as to be free for individual twisting, thus permitting the strap members of the loop to conform more readily to the angle of contact of the picker stick and so tending to impart flat contact of the stick across the whole width of the strap members. This, of course, reduces the concentration of strain on the members of the loop and so notably increases the effective life of the strap in action. It also tends to reduce wear and the necessity of frequent adjustments of the assembly.

We have found that further improvement of the life of the strap may be achieved by applying stiff reinforcing plates to the inner and outer faces of the strap members at both ends of the loop. These reinforcing plates are flared outwardly so that they apply a gradually increasing resistance to excessive flexing of the strap member, instead of localizing their bending strain by line contact as in the case of an insert interleaved between strap members.

An optional but desirable feature of the invention consists in chrome-plating the guide rod since this has been found to obviate scoring of the rod as has often happened heretofore, particularly when textiles are being woven of glass fiber.

These and other features of the invention will be best understood and appreciated from the following description of a preferred embodiment thereof, selected for purposes of illustration and shown in the accompanying drawings, in which:

FIG. 1 is a view in perspective of the whole assembly, and

FIG. 2 is a corresponding plan view thereof.

As herein shown the assembly includes a metal guide rod 10 having an elongated centrally-disposed lug 11 by which the rod is supported in horizontal position from a bracket (not shown) attached to part of the loom frame. The rod is of conventional shape except that the ice lug 11 is recessed or counter-sunk at 11' on the side toward the path of the picker stick to receive the attaching bolt head or nut in flush relation. Thus the danger of interference with the picker stick is obviated. We have also found it advantageous to give the rod a surface finish of chrome plate that has proved useful in preventing scoring.

At each end the rod 10 carries an attached bumper head 12 and movable on the rod, between these two heads, is the loop shape body of the check strap. This comprises a pair of superposed straps 13 and 14, of which the outer strap 13 is formed of heavy laminated webbing, such as rubberized canvas, and the inner strap 14 may be of high grade flexible leather, to inch in thickness or thereabout. At each end of the loop the straps 13 and 14 are reinforced by overlapping tongues or helpers lying inside the loop and tending somewhat to cushion the impact of the picker stick and reinforce the loop as a whole. The straps 13 and 14, together with the helpers 15, are perforated to fit loosely upon the guide rod 10 so that the loop may slide back and forth on the rod in checking the swing of the picker stick.

The perforated ends of the lop are compacted and further reinforced by inner clamping plates 16 and outer reinforcing plates 17. These may be formed of stilf fibrous or plastic material or metal. The inner plates 16 are notched in their inner edges to clear the guide rod 10, and the outer reinforcing plates are perforated to clear the guide rod and flared outwardly so as to exert a gradual or rolling reinforcing effect in restraining bulging of the loop under the impact of the picker stick. The end portions of the loop are all permanently bound together at each end by a group of three rivets 18 or other fasteners or a less number of rivets.

The bound ends of the loop extend beyond the guide rod 10 when they are connected by a tie member that converts the loop into D-shaped formation. As herein shown each end of the loop is perforated to receive a pair of hooks 20 located one above another and provided with adjustable collars 21.

A tie strip 22 is held under tension by and between the hooks 20. This strip may be of heavy rubberized webbing of substantially the full width of the strap members 13 and 14. It is partially divided into two equal sections by longitudinal slits 23 that run from the ends of the strip for about one third its length and terminate in punched holes serving to distribute stress at the inner end of each slit.

These slits convert each end of the strip 22 into two practically independent sections that may twist freely and independently to accommodate the angular stress imparted to the loop by impact of the picker stick and so facilitate the conformation of the check strap members to the angle of the stick in approaching full line contact. The capacity for free conformation of the check strap loop in this manner has been found to have an unexpected and unpredictable advantage in permitting higher speed operation of the loom without detrimental effect on the life of the check strap.

It is within the scope of our invention to employ a tie member consisting of two sections having no point of common connection such as is afforded by the portions of the strip between the slots 23 of FIG. 1.

The flared contour of the reinforcing plates 17 may be imparted to them initially or it may be created in the continued operation of the assembly by cold flow if the plates are formed of a synthetic resinous material.

Having thus disclosed our invention and described in detail an illustrative embodiment thereof, we claim as new and desire to secure by Letters Patent:

1. A picker stick check strap assembly comprising a guide rod, a U-shaped loop composed of superposed straps perforated at both ends and bodily slidably upon the guide rod, and a tie strip connecting the ends of said loop, independently of said guide rod and being of substantially the full width of the superposed straps of which the loop is composed, the said tie strap being slitted inwardly and longitudinally from both ends thus providing sections capable of twisting to accommodate the angle of the picker stick contact.

2. A picker stick check strap assembly comprising a guide rod, a U-shaped loop composed of a multiplicity of strap members arranged in overlapping relation and perforated at both ends for sliding engagement upon the rod, and means for holding together the perforated ends of the strap members including thin stiff reinforcing plates clamped against inner and outer faces of the assembled strap members, the outer of said plates being perforated and extending beyond the guide rod and being flared outwardly so as to exert a rolling reinforcing efiect in restraining bulging of the loop.

3. In a picker stick strap assembly, having a U-shaped loop slidable at its ends upon a fixed guide rod, a tie strip of heavy webbing extending under tension between the ends of the loop and including two longitudinal sections of substantially equal width partially separated whereby they may independently twist to accommodate the angle of the picker stick contact.

4. A picker stick check strap assembly comprising a chrome-plated guide rod, a flexible U-shaped multi-ply loop having perforated ends slidable on said guide rod, a longitudinally slitted tie strip fast between the ends of the loop, and external reinforcing plates fastened against the outer face of said perforated ends and flaring outwardly thereby applying a gradual restraint to effect flexing of the loop by movement of the picker stick therein.

5. A check strap assembly for controlling the stroke of an oscillating picker stick, comprising a guide rod having a central attaching lug countersunk on the side toward the picker stick and end bumpers, a laminated loop perforated at its ends to slide on said guide rod between the bumpers, and a tie member retained under tension between the ends of the loop having a plurality of sections separated for at least a portion of their length.

] Q 6. In a picker stick control assembly including a flexible U-shaped multi-ply loop for enclosing and limiting the movement of a picker stick; that improvement which comprises an elongated metal guide rod passing through the ends of the flexible loop and having a central attach- 15 ing lug countersunk on the side toward the body of the U-shaped loop to receive an attaching bolt in flush relation and out of the range of the picker stick movement.

References Cited in the file of this patent OTHER REFERENCES Textile Industries, vol. 126 No. 3, published by Y W. R. C. Smith Publishing Co. (Atlanta, Ga), March 1962 (p. 50 relied on). 

1. A PICKER STICK CHECK STRAP ASSEMBLY COMPRISING A GUIDE ROD, A U-SHAPED LOOP COMPOSED OF SUPERPOSED STRAPS PERFORATED AT BOTH ENDS AND BODILY SLIDABLY UPON THE GUIDE ROD, AND A TIE STRIP CONNECTING THE ENDS OF SAID LOOP, INDEPENDENTLY OF SAID GUIDE ROD AND BEING OF SUBSTANTIALLY THE FULL WIDTH OF THE SUPERPOSED STRAPS OF WHICH THE LOOP IS COMPOSED, THE SAID TIE STRAP BEING SLITTED INWARDLY AND LONGITUDINALLY FROM BOTH ENDS THUS PROVIDING SECTIONS CAPABLE OF TWISTING TO ACCOMMODATE THE ANGLE OF THE PICKER STICK CONTACT. 